+Hoiditthroughthegrapevine Posted February 15, 2018 Report Share Posted February 15, 2018 I need this for some calculations, I saw that someone had figured this out on a thread but I can't find it now. Thanks! Link to comment Share on other sites More sharing options...
3 RShara Posted February 15, 2018 Report Share Posted February 15, 2018 This post by jofwu should have everything you need for your calculations 3 Link to comment Share on other sites More sharing options...
1 Kurkistan Posted February 15, 2018 Report Share Posted February 15, 2018 Just now, Shqueeves said: Gravity on Roshar is .8 that on earth 0.7, actually. 2 Link to comment Share on other sites More sharing options...
1 king of nowhere Posted February 15, 2018 Report Share Posted February 15, 2018 3 hours ago, RShara said: This post by jofwu should have everything you need for your calculations This makes me think. The size of roshar continent is roughly that of asia, and the distance between shinovar and alethkar roughly the one between europe and china. So maybe there was on roshar a Cristopherin Chiken who, after miscalculating the distance involved, attempted to reach alethkar from shinovar sailing westward. there was no continent to discover, and he sunk in a highstorm anyway. 1 Link to comment Share on other sites More sharing options...
0 Nashan’Elin Posted February 15, 2018 Report Share Posted February 15, 2018 Yes, the gravity of Roshar is 0.7 that of earth, so acceleration due to gravity would be about 6.86 m/s^2, I think 1 Link to comment Share on other sites More sharing options...
0 RShara Posted February 15, 2018 Report Share Posted February 15, 2018 Gravitational acceleration isn't directly proportional, I don't think? So .7 Earth Gravity wouldn't necessarily be 70% of 9.8 m/s^2. I can't remember for sure. Anyway, the post above gives the mass of Roshar, which will allow him to calculate the correct gravitational acceleration. Link to comment Share on other sites More sharing options...
0 +Hoiditthroughthegrapevine Posted February 15, 2018 Author Report Share Posted February 15, 2018 Awesome, thanks all! Thanks for dumping @Jofwu's calculations of the physical characteristics of Roshar @RShara, really helpful stuff. I am working on some calculations for conjoined fabrials. I realized that after the first couple of answers came in that the proportional gravity of Roshar was stated by Khriss in Arcanum Unbounded (duh), but it's rad to have all of those calculations that Jofwu did in one place like this. Link to comment Share on other sites More sharing options...
0 digitalbusker Posted February 22, 2018 Report Share Posted February 22, 2018 On 2/15/2018 at 3:05 PM, king of nowhere said: This makes me think. The size of roshar continent is roughly that of asia, and the distance between shinovar and alethkar roughly the one between europe and china. So maybe there was on roshar a Cristopherin Chiken who, after miscalculating the distance involved, attempted to reach alethkar from shinovar sailing westward. there was no continent to discover, and he sunk in a highstorm anyway. Isn't that basically the story of the Wandersail? Link to comment Share on other sites More sharing options...
0 digitalbusker Posted February 22, 2018 Report Share Posted February 22, 2018 On 2/15/2018 at 1:05 PM, RShara said: Gravitational acceleration isn't directly proportional, I don't think? So .7 Earth Gravity wouldn't necessarily be 70% of 9.8 m/s^2. I can't remember for sure. Anyway, the post above gives the mass of Roshar, which will allow him to calculate the correct gravitational acceleration. It is. The post above uses the given 0.7g surface gravity to calculate the planetary mass. Link to comment Share on other sites More sharing options...
0 RShara Posted February 22, 2018 Report Share Posted February 22, 2018 2 hours ago, digitalbusker said: It is. The post above uses the given 0.7g surface gravity to calculate the planetary mass. Hmmm. Weird. I thought it followed the inverse square law. On 2/15/2018 at 9:58 AM, Shqueeves said: Gravity on Roshar is .8 that on earth .7 Link to comment Share on other sites More sharing options...
0 digitalbusker Posted February 22, 2018 Report Share Posted February 22, 2018 (edited) 3 hours ago, RShara said: Hmmm. Weird. I thought it followed the inverse square law. It does, but the acceleration we refer to as g is the calculated value at sea level. (Or rather at the defined planetary radius.) Edited February 22, 2018 by digitalbusker Preemptively self-pedantic Link to comment Share on other sites More sharing options...
0 +hwiles Posted February 23, 2018 Report Share Posted February 23, 2018 @RShara the only knit-pick I have with your data, which is astonishingly complete, is that I would add the caveat that the weird precession in Roshar's moons is ultimately due to the fact that Roshar (the planet) exhibits an unstable orbit with its nearby bodies. In other words, in the future, be it distant or near, one or more of Roshar's moons will either slam into its surface, or be ejected from orbit unless something very drastic happens. Many Cosmere fans forget this fact when first attempting to make orbital projections about Roshar; I can't recall the location of the link off-hand, but I believe Peter has stated this outright in the past. This assumption leads to a very deep rabbit hole of Lagrange points and stable orbits that really just isn't applicable; I wish you all the best in developing better calculations than your predecessors; TLR knows I didn't get very far... Link to comment Share on other sites More sharing options...
0 RShara Posted February 23, 2018 Report Share Posted February 23, 2018 14 minutes ago, hwiles said: @RShara the only knit-pick I have with your data, which is astonishingly complete, is that I would add the caveat that the weird precession in Roshar's moons is ultimately due to the fact that Roshar (the planet) exhibits an unstable orbit with its nearby bodies. In other words, in the future, be it distant or near, one or more of Roshar's moons will either slam into its surface, or be ejected from orbit unless something very drastic happens. Many Cosmere fans forget this fact when first attempting to make orbital projections about Roshar; I can't recall the location of the link off-hand, but I believe Peter has stated this outright in the past. This assumption leads to a very deep rabbit hole of Lagrange points and stable orbits that really just isn't applicable; I wish you all the best in developing better calculations than your predecessors; TLR knows I didn't get very far... Hey now, it's not my data I wish my brain worked well enough to come up with that. I mean I could...but it would involve hours and hours of finding the right equations, paper, and pencils. My physics classes were a LONG time ago, and while I remember the concepts pretty well, a lot of the technical equations have been erased from my memory! The credit goes to jofwu and a few others. Also, they have worked on the moon issue, and they agree that the moons are super screwy. Here is the first portion, that doesn't involve OB spoilers. Here is the second portion that involves OB spoilers. Link to comment Share on other sites More sharing options...
-2 Shqueeves Posted February 15, 2018 Report Share Posted February 15, 2018 Gravity on Roshar is .8 that on earth 1 Link to comment Share on other sites More sharing options...
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+Hoiditthroughthegrapevine
I need this for some calculations, I saw that someone had figured this out on a thread but I can't find it now.
Thanks!
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